1. Field of the Invention
This invention relates to vehicle differentials and, in particular, to a differential and method for assembling a differential that enables relatively easy alignment and secure positioning of bearings within the differential.
2. Discussion of Related Art
Differentials are provided on vehicles to divide power provided at two outputs. A wheel differential enables a pair of wheels on a common rotational axis to rotate at different speeds while the vehicle is turning. A conventional differential includes a differential carrier that receives a power transmission shaft having a pinion gear mounted at one end. The pinion gear is disposed within the differential and meshes with a ring gear that is coupled to, or integral with, a differential case. The case supports a plurality of bevel gears that transmit torque to a pair of axle half shafts that are in turn coupled to a corresponding pair of wheels.
The differential case is supported for rotation within the differential carrier by a pair of bearing assemblies. During assembly of the differential, each of the bearing assemblies must be properly aligned by moving the bearing assembly axially inward and outward along the axis of rotation. Conventional bearing assemblies are typically positioned and aligned within the differential carrier using threaded bearing adjusters that urge the bearing assemblies axially inward and outward. Bolts, clips, cotter pins or metal stampings are used to maintain the position of the bearing adjusters within the differential once a predetermined alignment position is reached. This configuration has a significant disadvantage. The bearing adjusters typically have a finite number of lugs (e.g., twelve to sixteen) projecting therefrom. The bolts, clips, cotter pin or stampings are inserted into one of the lugs or in between a pair of lugs to retain the bearing adjuster in place. As a result, the bearing adjuster, and therefore the bearing assemblies, can only assume certain angular and axial positions thereby limiting the ability to optimally align the bearing assemblies within the differential.
The inventors herein have recognized a need for a differential and method of assembling a differential that will minimize and/or eliminate one or more of the above-identified deficiencies.
The present invention provides a vehicle differential and a method for assembling a differential.
A differential in accordance with one aspect of the present invention includes a differential carrier disposed about a first axis and a differential case disposed within the differential carrier. A bearing assembly is disposed about the first axis between the differential carrier and the differential case. The bearing assembly allows the differential case to rotate within the differential carrier. The differential carrier includes a first plurality of threads disposed on a radially inner surface. The bearing assembly includes a cup having a second plurality of threads disposed on a radially outer surface that are configured to engage the first plurality of threads.
A differential in accordance with a second aspect of the present invention also includes a differential carrier disposed about a first axis and a differential case disposed within the differential carrier. A bearing assembly is again disposed about the first axis between the differential carrier and the differential case to allow the differential case to rotate within the differential carrier. The differential further includes a deformable member coupled to a cup of the bearing assembly. At least a portion of the deformable member is deformed and inserted into a slot in the differential carrier upon alignment of the bearing assembly within the differential carrier.
A method of assembling a differential in accordance with the present invention may include the step of providing a differential carrier and a differential case disposed within the differential carrier wherein the differential carrier and the differential case are disposed about a first axis and the differential carrier has a first plurality of threads on a radially inner surface. The method may further include the step of inserting a bearing assembly between the differential carrier and the differential case wherein the bearing assembly includes a cup having a second plurality of threads disposed on a radially outer surface and configured to engage with the first plurality of threads on the differential carrier. The method further includes the step of rotating the bearing assembly until a predetermined alignment position is reached. The inventive method may also include the steps of affixing a deformable member to the cup of the bearing assembly, deforming at least a portion of the deformable member after reaching the predetermined alignment position, and inserting the at least a portion of the deformable member into a slot in the differential carrier.
A differential in accordance with the present invention is advantageous. The bearing assembly between the differential carrier and differential case may be rotated to align the bearing assembly and may assume an infinite number of angular positions and axial positions providing greater control of alignment than in conventional differentials. The deformable member provides a relatively inexpensive method of securing the position of the bearing assembly upon alignment of the bearing assembly within the differential.